The prefrontal cortex plays an executive role in the expression and control of emotion and goal-directed behaviors; yet, it is one of the last brain regions to mature. Of great concern is how risky, impulsive behaviors such as binge alcohol drinking in male and female teenagers may impacts maturational processes (e.g., myelinization) within the prefrontal cortex to have long-lasting consequences on psychiatric health. This proposal uses an innovative and clinically relevant model to elicit (and control) frequent bouts of voluntary binge drinking in male and female rats to investigate the causal effects, underlying mechanisms, and reversibility of adolescent binge drinking myelinated axons in prefrontal cortex.